Heretofore, two basic types of connectors have been employed for attaching ends of flexible hoses to a rigid threaded pipe. The flexible hoses have various applications, for example, on vehicle air conditioning systems Freon is circulated through the hoses.
The first type of fitting is generally referred to as a "crimp-type fitting". This type of fitting generally comprises a tubular ferrule having an inside diameter substantially equal to the outside diameter of the flexible hose end. The ferrule has a central tube secured therethrough having a barbed end which fits on the inside of the flexible hose. A threaded coupling is rotatably secured to the other end of the tube. When attaching the coupling to the end of the flexible hose, a tube is inserted inside the hose and the ferrule slips over the outside of the hose. It is necessary to crimp the ferrule over the outside of the hose urging the flexible hose into engagement with the barbs on the tube to form a seal between the tube and the flexible hose.
The other type of fitting comprises a tube having a barbed end which is inserted into the end of the flexible hose and a swivel coupling connected to the other end. A hose clamp is secured about the end of the hose over the area of the hose adjacent the barbs to urge the hose into engagement with the barbs. Problems have occurred with the use of this type of coupling in that the vibration from automobiles or equipment tends to loosen the hose clamp and thus allow the pressure from the fluid being carried by the flexible hose to blow out the tube thus causing a failure of the hose. This often leads to a shutdown of the equipment and could create a hazardous condition.
When the hoses are being used on air conditioning systems for automobiles a leak of this nature will allow the Freon to escape into the atmosphere. The average automobile system has between three and six pounds of Freon therein. The Environmental Protection Agency (EPA) has determined that the Freon is hazardous to the environment since the Freon tends to break down the ozone layer which protects the Earth's surface from excessive ultraviolet rays of the sun. The EPA has determined that the hose clamp type connections are not satisfactory for preventing leaks in Freon systems.
Heretofore, devices to crimp the ferrule of a coupling onto an end of a flexible hose have comprised large, stationary units having a segmented collet which is urged radially inwardly by a spacer ring which is moved by a hydraulic or air type cylinder. The hydraulic or air pressure must be supplied from a separate power source. These devices are not only expensive and impractical for the average small repair shop to use but also cannot be used as a hand tool under the hood of a vehicle.
In making repairs it is desirable to repair only that portion of the system which is leaking, in that removal of further connections may cause further problems within the system. Heretofore, it was necessary to remove both ends of the hose from the system of the vehicle to make the proper repairs to one end of a hose if a crimp type coupling was used.
Heretofore, no devices have been known which could be employed to satisfactorily crimp the ferrule onto the flexible hose under the hood of an automobile or on the vehicle itself. Devices heretofore utilized have comprised a "bolt cutter" configuration requiring long handles which can not be satisfactorily used in a limited area on the automobile. Further, the toggle or "bolt cutter" configuration does not have a uniform force throughout the range of movement of the handles and causes an oblong deflection of the ferrule as it is crimped onto the hose. This creates a void or weak spot due to uneven pressure between the ferrule and the hose which can leak. It is necessary to provide a tool which will give a uniform pressure radially inwardly about the entire circumference of the ferrule to urge the hose into engagement with the barbs on the tube.